Different industrial applications require insertion of various types of metal fasteners into thermoplastics components with high pull-out resistance, rotational resistance and resistance to vibration and back-out torque. An example of these known techniques is found in U.S. Pat. No. 4,488,672 assigned to the assignee of this invention entitled "Thermal Press Having Insert Driving Air Biasing Mechanism". This referenced patent discloses a readily adjustable press which insures consistent and uniform high quality installation of metal inserts into thermoplastics material under varying conditions. As is known, such thermoplastics workpieces are normally temporarily located in a fixed jig or other suitable device below the insertion mechanism.
In such applications it is particularly desirable to have an insertion mechanism which will provide for installation of inserts of workpieces of widely varying depth, thereby allowing an operator to place a workpiece below the inserter even with a so-called "deep" workpiece.
In such applications, it is also desireable to provide, if possible, for retraction of the movable parts of the installation equipment to permit movement and changing of the workpiece in a quick and easy manner.
Yet further problems which have been encountered in conventional insert installation equipment include complexity of design in known mechanisms which require multiple valving, logic timing and interlocks to a controller for sequencing and controlling independent motions of parts of the installation equipment and yet further complexities introduced by critical design features such as bearings for such equipment providing for insert installation having close tolerances.
Accordingly, it is an object of this invention to provide a new and improved machine for the installation of inserts into a workpiece which machine is of a significantly simplified design providing consistent quality and reliability, reduced cost in its manufacture and trouble-free operation under normal production conditions.
Another object of this invention is to provide for such a machine wherein a multiplicity of independent motions are controlled by a single reciprocating stroke of an operating cylinder to effect insert installation into a workpiece and return of the machine components at the end of the cycle in readiness for the next operating cycle.
A further object of this invention is to provide such a machine which is particularly suited for a simplified control whereby even a single control may be used to control the operation of the machine while eliminating conventional requirements for normal sequencing controls.
Yet another object of this invention is to provide a machine of the type described featuring controlled guidance of inserts during insertion by an extensible and retractable insert guide tube which allows clearance for workpiece movement or removal between strokes.
A yet further object of this invention is the provision of such a machine which effects a positive drive in opposite directions of reciprocation of the main operating components to minimize binding and to provide continuous drive control of the operating components.
Other objects will be in part obvious and in part pointed out in more detail hereinafter.